Career
Flannery"s usual position was loose/lock forward although he also played as a utility back row forward, Stand-off half or centre. After retiring Flannery administered the Sunshine Coast Falcons of the Queensland Cup. National Rugby League
Flannery made his National Rugby League debut for the Sydney Roosters in Round 14 of the 2000 NRL season against the Wests Tigers at Campbelltown Stadium on 7 May.
He was first selected to play for Queensland in Game II of the 2002 State of Origin series at Australia and New Zealand Banking Group Stadium on 5 June.
Flannery played for the Roosters from the interchange bench in their 2002 NRL grand final victory over the New Zealand Warriors, scoring a try. Flannery played at centre in Sydney"s victory.
He again played from the interchange bench for the Roosters in the 2003 NRL grand final which was lost to the Penrith Panthers. Flannery played for Queensland in all three matches of the 2004 State of Origin series.
He played for the Roosters at lock forward in their 2004 NRL grand final loss to cross-Sydney rivals, the Bulldogs.
Super League
In 2007, Flannery signed for Saint Helens on a three and a half year deal. Flannery was brought in as a direct replacement for fellow Australian Jason Hooper who had to retire following problems with his shoulder. Flannery described himself as a hard worker and strong in defence.
"I also like to add a bit to the ball playing by taking it up at first or second receiver.
I also like to run good lines into holes." He commenced his Knowsley Road career in July, 2007, after recovering from a broken legal He played in the 2008 Super League Grand Final defeat by the Leeds Rhinos.
After returning to Australia, Flannery became chief executive of Queensland Cup team the Sunshine Coast Falcons.